#include<iostream>

using namespace std;

class Solution {
public:
    int mySqrt(int x) {
        if (x < 1)
        {
            return 0;
        }

        int left = 1, right = x;
        while (left < right)
        {
            long long mid = left + (right - left + 1) / 2;
            if (mid * mid <= x)
            {
                left = mid;
            }
            else
            {
                right = mid - 1;
            }
        }

        return left;
    }
};

int main()
{
    return 0;
}